Lighting device



E. D. TILLSON.

LIGHTING DEVICE.

APPL ICATION FILED MAYZI, 1919.

1,360,825. Patented Nov. 30, 1920.

2 SHEETS-SHEET l- E. D. TILLSON.

LIGHTING DEVICE.

APPLICATION FILED MAYZI. I919.

1,360,825, mm Nov. 30,1920;

2 SHEETSeSHEET 2- flak/47471220 UNITED STATES EDWIN D. TILLSON, OFEVANSTON, ILLINOIS.

PATENT OFFICE.

LIGHTING DEVICE.

Application filed May 21,

To all whom it may concern:

Be it known that I, EDWIN D. TILLSON, a subject of the King of GreatBritain, residin at Evanston, in the county of Cook and btate ofIllinois, have invented a certain new and useful Improvement'in LightingDevices, of which the following is a specification.

My. invention relates to lighting devices, especially those employinghigher powered lamps, for example, 500 watt nitrogen filled lamps inwhich the filament is usuallyquite concentrated and consequently is aptto pro duce disagreeable images in the associated reflector. The objectof the invention is to produce a fixture which will utilize to thefullest extent the energy used for producing V which the light'and atthe same time protect the eyes of those within range- It is also myobject to provide details of construction which contribute to thegeneral efliciency of the device. Among these details are: A convenienthanger for suspending the translucent element and convenient means forsuspending the deflector blades near the lower .part of the structure.

I obtain my objects by the structureillustrated in the accompanyingdrawings in Figure 1 is an elevation of the complete device, chiefly incentral or axial section.

Fig. 2 is a bottom plan view omitting'the reflector. I

Fig. 3 is a fragmentary side elevationshowing the dropped position ofthe deflectors.

. F i 24 is a top plan sectionon the line HI ig. 1. a

Fig. 5 is a perspective view of the hookshaped hanger employed forsuspending the translucent elements.

Like numerals denote like parts throughout the several views. 7

In the form shown in the drawings for illustrating the principle of theinvention, the light source 1 is a filament mounted within a bulb 2which screws into a socket .3 in accordance with standard construction.

' It may be assumed that the bulb and fila- Specification of LettersPatent.

' may be varied,

Patented Nov. 30, 1920. 1919. Serial No. 298,706.

ment which accordin to the present design, has a cylindrical portion 6and an upper port on 7. The portion 7 is of very light denslty, locatedin position to intercept and diffuse the rays directed toward thereflector. It will be understood that in high powered lamps, like thosepreviously mentioned, the filaments are ordinarily quite concentratedwith the result that the reflected rays present to the eye an image ofthe filament, and this is so bright that it is disagreeable ifnotinjurious. In my device the upper portion 7 is of such light densitythat the rays will not be appreciably dimmed but simply difl'used enoughto prevent the reflector from showing an image of the filament. Theaction is illustrated bythe ray A, Fig. 1, and the diffused rays A. vThe portion 6 of the translucent element is of greater density; Inpractice, for commercial and manufacturing reasons, the increase indensity isproduced by simply firing a band 8 of enamel onto the outsideof the portion 6 which is otherwise of the same character as portion 7.

While the vertical dimensions ofthe cylindrical portion of thetranslucent, element it may be stated in general that its elevationat'the center is about the same as the elevation upper edge being highenough to intercept the rays which would otherwise escape the lower edgeof the reflector, and the lower edge being low enough to confine thedirectrays to a moderate size circle beneath the lamp.

The translucent element is suspended by hangers here shown in the formof hooks 10 shown in perspective in Fig. 5. The hooked lower end engagesthe lower edgeof the translucent element, and the upper endis'yieldingly supported by leaf springs 11, 11 adapted to rest upon thetop of the reflector as shown near the center of Fig. 1. The result ofthis construction is that the translucent element is held snugly incontact with the reflector and hence there is no vibrationacharacteristic of considerable advantage in factory buildings where themachinery produces a constant and sometimes considerable vibration ofthe building. This type of suspension has another advantage in that whenthe translucent element is removed, the hangers automatically swinginward toward the. vertical converges upward and inward, and is of thefilament, the

axis of the device, thusfacilitating rec-hangingand removal of thetranslucent 'elementJ The position of the hangers \vhennot in activeposition is indicated by the dotted lines at the left of Fig. 1.

' -"While the cylindrical element 6, i 8 is translucent, nevertheless,with high powconcentrated filaments an ered lamps and on the-insideof itwhich image is formed standing even at a con- For example, a ray such'agreeable "effect is prevented by means of 14." These are arrangedinvertical planes located in the openingatthe lower edge of thetranslucent memben They are locatedbeneath the lamp, but by preferenceare 'so'formed-as tofol-low the contour of the lamparound' the bottomportion thereof.

i Lccording to the present design there are three of these deflectorsand they are so positioned thatthey will intercept the'rays v "(as Fig.l)" whichwould otherwise form an image of the filament. being arrangedin vertical planes, will practi'cally causefho' shadows directly beneathThese deflectors,

" and they will not cause any perceptible shadows-1n a lateral direct onfor the reason vice. In the preferredconstruction the dethat the areas'which mightbe shadowed by them will be lighted either directly' or byreflection from-some other part of the defl'e'ctors are attached to thelowerend of the ":movableto permitithe deflectors to down a cated inFlg.3. V In practice,

hangers 10.

element, it is desirable 'that the pin 15, shown 7 swing bout the pin 15as a-pivot. The dropped position of the deflectors isj'indiappreciableextent.

would be visible and hence a source of 'ani To" facilitate removal ofthe lamp -ithout" disturbing the translucent -"at'the'left of Figs. 1and 3 be a permanent v pivot pin, the other pins 1 6, 16 being rewhenthe parts are assembled as shown in Fig. 1, the rays passing upwardtoward the'i'eflector will, most of them, first pass through the portion7 of the translucent element and be diffused sufficiently to prevent theformation of an image on .the reflecton'but without being dimmed toanyThe rays which are directed horizontally or somewhat below thehorizontal are in parttransmitted and in 'part reflected by the portion6, 8 of greater density.

However, the image which is formed on the inner surface of the portion 6is intercepted by the deflectors and by? them reflected. By the time thelight reaches the eye of an observer in almostany position relatively tothe device as a whole, it

will be so broken up and-diffused thatit will be, as it were,homogeneous and therefore? create a pleasing impression and at the sametime take full advantage of the electric energy consumed in thefilament;

' Having thus 1 described my invention what I claim as new and desire tosecure by Letters Patent, is

1. Av lighting devlce having alight source; a reflectorabovexsaldsource, and a'translu- 'c'entelement on the general level ofthe light source and extending up approximately to the reflector, saidelement being open at the bottom and the lower portionbei-nguofconsiderable density, the upper portion being of verylightdensity .for partially diffusing the rays 'directedtoward the reflector.

2. A lighting device having a light source, a reflector above saidsource, a'translucent element surrounding said source, said trans lucentelement being open at the bottom,

and hooks suspended from the reflector and adapted to engage the loweredge ofthe translucent element, said hooks being yieldingly supportedwhereby they tend to press upward upon the translucent element and holdit in close contact with the reflector.

scribed my name.

- eDwia-anmso 9.0 In witness whereofl have hereunto sub-.

